The President or Defense Secretary must have issued the order, which remains classified, given that an “‘Execution begins when the President decides to use a military option to resolve a crisis,’ according to Joint Publication 5-0 on Joint Operation Planning,” FAS said. “Only the President or SecDef can authorize the CJCS [Chairman, Joint Chiefs of Staff] to issue an execute order (EXORD).”

The hackers targeted the Navy Marine Corps Intranet, the unclassified network used by the Department of the Navy to host websites, store nonsensitive information and handle voice, video and data communications, according to the Wall Street Journal. (photo via navy.mil)

U.S. officials said Iran hacked unclassified Navy computers last summer in an escalation of Iranian cyberintrusions targeting the U.S. military, according to the Wall Street Journal.